Form for working on sheets



Aug. 22, 1961 w. F. GoLDlNG FORM FoR WORKING on SHEETS Filed July 13, 1960 I3 Il /0 United States Patent; Q

y 2,996,983 v i FDRM FOR WORKING 0N SHEETS -William Frank Golding, 22 P .alrys Close, Stoke Bishop, -Bristol 9, England Filed `luly 13, 1960, Ser. No. 42,529

Claims priority, application Great Britain `Iuly 16, 1959 5 Claims. (Cl. 101''384) g This invention relates to forms for working on sheets and being of the'kind wherein a plurality of diesv are secured to a support member which is removably'connected to a pressure member or platen of a press.

4The dies may be embossing dies or dies'for performing a cutting, creasing or like operation on Athe sheets. The work done by such dies on the sheets must be in register withcertain data on the sheets. For instance, embossing work must register with existing -printing-on the sheets. Usually such register must be of..a veryhigh order of accuracy, especiallyin the embossing l of printed matter. 1 To achieve good registerit is known. to-build u'p theformof a'plurality of vrelatively small dies, each appertaining toa particular unit of the work,A and to Varrange for the'dies to be `individually adjustable for position 011 said supportmember. l Certain known devices for connecting the dies to' the' supporting member comprise clamps engaging theedges of the dies, but apart from the expense involved in soin'e oft-these-devices, they have the disadvantage of taking up space at the edge of lthe-dies with the consequence that they cannot be used in cases where the dies have tobe situated in close proximity to each other. Hitherto,the

space` diiculty had been overcomeby glue'ing the dies to a flat surface of the supporting member and. positioning thedie'swhile'the glue isv'still 'soft' and therefore amenable to's'uch adjustment being made. However, this-izarocedure requires quite exceptional skill on' the part of the operator in thathe has to position the -dies during Ithe relatively short period in which the glue iss ufliciently'soft for the purpose. Also, the glue may degenerate after some period of `use of the form. This is particularly so .in ernbossing work Iwhere relatively high pressure, and in some cases heat, are required lfor the -work.

It is an vobject of this invention to provide a relatively simple and inexpensive construction for adjustably fastening the dies in positionon the supporting member;

A further object of this invention is to provide for the attachment of the dies to the supporting member in a way allowing close proximity between adjacent dies but avoiding the difculties of the glueing process described.

According to this invention I provide a form for Working on sheets and for use on a platen of -a press, comprising a plate connectable to said platen in spaced parallelism with the pressure surface thereof, a gap being defined between said pressure surface and the surface of the plate adjacent thereto, a plurality of plate-shaped embossing dies situated `at the surface of said plate remote from said pressure surface, a locking plate situated in said gap in a position opposite each of said dies, the locking plates being substantially congruent with the respective dies, at least two holes provided in said plate in a position between each die and its associated locking plate, a screw passing through each of said holes and co-operating to clamp the die to the locking plate, said screws being tightenable to clamp the die to the plate and being releasable to release the die, said holes being dimensioned to have a clearance with said screws, and the position of the die being adjustable relative to said plate to the extent of said clearance when said screws are released.

One construotional example of a form according to this invention will now'be described with-ereference to the a .c`:'' y companying drawing wherein:

FIG. 1 is a sectional elevation of the form as situated in its operative position on a'platen. t, 11 FIG. 2 is a plan view of theform andl -a part ofjthe platen. l ,.i t

lFIG. 3 is an enlarged section on the line PIG. 2.

FIG. 4 is an underside view` of FIG. il.

Referring to the Adrawing', there* i's fshown Y a forniA comprising a plurality Vof plate-shaped embossing dies 10 each having a hat rear surface 11 (FIG; 3) and a front or working surface 12 having moulded recesses or pro--v trusions 13 dening a pattern, for instance as denoted A14gA (FICi.l 4), to be embossed. `Eaclidie 10 is provided at; positions clear of the pattern 14 With at least two holes- 1'5A extending through-the thickness of the plate shape-of the die. Further, in respect of eachdie 10 there'is pro-- vided a locking platel 16 dimensioned to -cover an area substantially congruent with that of the die 10, and thev locking plate 16 is provided with tapped holes 17 in posii.

tions corresponding to the holes 15 in the die 10.--

The dies 10 and the corresponding locking plates-'16l are positioned on opposite sides of a-suppoitin-g plate 18 and the dies' 10 are connected to their Arespective locking plates 16 by headed screws 19 passing through 'pre-'formed clearance holes 22 in the supporting plate 18. #Heads 20 of'the screws -19 are situated 'at the frontv faces 12 of-v the dies 10 and threaded portions 21' of the screws 19; engage the tapped holes 17 in the locking'plates '16." The locking Aplates 16 co-operate -to-clamp-thefd'ies 10 'tog the supporting plate 18 when theserews 19 are tightened? The-screw heads 20 are countersunltintothe front sur-l faces 12' of the dies 10 so as not to constitute -an obir structive projection. Y The purpose of the clearance holes 22 inthe supporting plate 18 is to provide -for the adjustment of -the position of the vdies 10 on the supporting plate 18,- and it will'l be seen that any one of the dies 10 can bel adjusted for position independently ofthe other dies 10 simply upon release of .the screws 19 appertaining to this one die.

The area of the supporting plate 18 isA of course such" I that all the dies 10 required for a particular embossing operation can be assembled thereon. The supporting plate 18 is in turn supportedon a platen 23 ofa press in such a manner that the surfaces of the locking plates 16 remote from the supporting plate 18 bear against the pressure surface 24 of the platen 23. The locking plates 16 are all of the same thickness so as to be seatable uniformly against the pressure surface 24. The object of said substantial congruence between the dies 10 and the locking plates 16 is to ensure that each die is supported against the pressure surface 24 over the whole area of the die, this being important since the supporting plate 18 itself does not touch said pressure surface 24 but the embossing pressure is transmitted through the plate 18.

The dies 10` may each comprise a body 25 (FIG. 3)

of a relatively soft lead-based metal, e.g. type metal, provided at the front surface 12 with a working layer 26 of a harder metal, eg. copper, Iwhich may in turn be nickel or chromium plated. The position of theholes .15 is determined at the time when the dies 10 are made and the mould from which the body 25 is cast is provided at the positions of the holes 15 with substantially conical projections producing corresponding dimples in the body 25. Later these dimplesy serve as a start for the drilling of the holes 15, and the dimples are such that after drilling there remains a truste-conical recess 27 for the reception of the screw heads 20 which are themselves of the frustoconical or countersunk type. Since the working layer 26 covers the recesses 27 the screws 20 do not wear out the die 10 during repeated releasing and tightening.

The shape of the embossing patterns is usually such that space for the holes 15 can be found without enlarging the areacovered bythe die 10.- l 1n some cases it is possible to provide a hole at the interior .of a pattern, for instance, as shown `at 28`i1 1 FIYG. 4. In consequence the dies ltl'can be positioned in very close relationship, in fact, lthe dies lllneed .only bespaced apart bythe amount of adjustment provided for by the clearance holes 22.

i The supporting plate 18 may oe made of a light metal alloy, or of a light synthetic material, thereby to reduce weight. The holes `22 are drilled where required by the dieV positions and can be marked ott easily `from a sheet to be embossed .on which the hole positions are shown. After use, the form -is usually left intact for future runs of the same work. In view of the relative cheapness of the plate 18 this Iis quite-.economical and the user is not faced with 'the diliiculty of either dismantling the dies or having an expensive form standing idle.

Y The procedure of adjusting the dies is to take impressions yof the embossing on successive sheets of cardboard to be embossed and inspect each sheet for accuracy of register. 'Ihepform is withdrawn from the platen 23 after each .such ,impression and the die positions corrected until the required order of accuracy is obtained. In other words, the .form `must be capable of being conveniently moved into Aand from the operative position and must be provided with the necessary means for being movably supported `on the platen 23 and being lockable thereto. However, in order to reduce the cost of stand matter these means are notprovided directly on the plate 18 but are d eiined by a rectangular chase 30 to which the plate 18 is `secured by lugs 31 provided on the plate 18 being connected to the chase 30 by screws 32. The chase 30 itself is supported for movement from and into the operative position on the platen 23 by rollers 33 provided thereon and engaging side members 34 kof the chase. Means (not It will be appreciated thatthe invention is not limited to the use of embossing dies. Dies such as cutting and creasing dies or combined embossing and cutting dies are equally capable of being used for building a form according to this invention.

WhatI claim and desire to secure by Letters Patent is:

l. The combination with the platen of a platen press, of a form for working on sheets' comprising a plate connected to said platen in spaced parallelism with 4the pressure surface thereof, a gap being defined between said pressure surface and the surface of the plate adjacent thereto, a plurality of plate-shaped embossing dies situated shown) are provided for locking the chase 30 into the operative position. The chase 30 is dimensioned to support the plate 18 Ain the necessary position of Aspaced parallelism relative to the pressure surface 24, i.e. a position dening between the plate 18 .and the surface 24 a gap 35 (FIGS. 1 `3) for the locking plates 16. A bar 36 extending across the chase 30 and removably secured to opposite end members 37 thereof serves to support the central portion of the plate 18 against downward bowing, the plate 18 being connected to the bar 36 by a screw 38, and a spacing collar 39 being provided to lill the gap 35v around the screw 38.

at the surface of said plate remote from said pressure surface, a locking plate situated in said gap in a position `opposite each of said dies, the locking plates being substantially congruent with the respective dies, at least two holes provided in said plate in a position between each die and its associated locking plate, a screw passing through earch of said holes and co-operating to clamp the die to the locking plate, said screws being tightenable to clamp the die tothe plate and being releasable to release the die, said holes being dimensioned to have a clearance with said screws, and the position of the die being adjustable relative to said plate to the extent of said clearance when said screws are released.

2. The combination according to claim 1, said screws each comprising a head situated at a surface of the die remote from said plate, and a shank passing through a hole in the die and terminating in a screw-threaded portion engaging a tapped hole in said locking plate. l

3. The combination according to claim 2, wherein said head is of frusto-concal shape situated in a corresponding frusto-conical recess of said hole of said die.

4. The combination as claimed in claim 3, wherein said die comprises a pre-formed dimple including said frustoconical recess.

5. The combination as claimed in claim l, additionally including a chase comprising a rectangular frame releasably Aconnected to said platen, means for rele'asably connecting said supporting plate to said chase in a position substantially within said frame, said frame being dimensioned :to support said plate in said position of spaced parallelism thereof when the chase is connected to said platen.

References Cited in the tile of this patent UNITED STATES PATENTS 576,711 Abelmann Feb. 9, 1897 

